The overall goals of the Core Center are to: bring together 13 investigators working on different aspects of hearing and communication disorders, increase the efficiency and productivity of their individual efforts and ongoing collaborations, integrate investigators studying basic hearing mechanisms in animals with investigators studying human hearing impairment, and provide opportunities for newly developing collaborations to reach fruition. The investigators participating in this application represent an extraordinary range of hearing science from anatomy and physiology of hearing in insects to the psychoacoustics of complex sound perception in humans. Existing projects include sound localization in bats and birds, prey-predator interactions in insects and bats, hair cell regeneration in fish and birds, recovery of hearing and vocalizations in birds following hair cell regeneration, the precision of time resolution in bats, birds, normal, hearing-impaired, and aged humans, and the ontogeny of auditory time resolution in animals from insects to birds. Several projects focus on psychophysical or physiological aspects of temporal processing in either normal-hearing or hearing-impaired humans. The research base consists of a total of 14 research projects on different aspects of auditory research: six NIDCD R01s, one NIA and one NIMH R01, one ONR MURI grant, one NSF grant, and four NIDCD R03s. Several projects are focused on auditory "specialists" organisms showing unusual sensitivities and novel auditory mechanisms and adaptations. All investigators are attempting to explain complex auditory behavior by discovering, modeling, or gathering data to test anatomical and physiological mechanisms. While each of these projects is independent, there are multiple areas of interface, overlap, and collaboration among investigators. Significant opportunities to advance auditory science exist at the interfaces of these projects. Providing the resources to realize these opportunities is the purpose of this P30 application.